• Journal of Korean Society of Forest Science
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• v.89 no.4
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• pp.502-512
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• 2000

Old-growth development for two different second-growth northern hardwood stands in the North America was evaluated with a computer simulation. The two sites compared were a representative 77 year old even-aged stand (Phelps) with heavy dominance by pole size classes, and an older uneven-aged stand with some existing old-growth structural features (Wildcat Creek). Each stand was evaluated in its natural progress toward old-growth structural conditions with stand structure, size distribution of live and dead trees, percent stand area in canopy gaps, and visual canopy profile and overhead view. The Phelps stand reached the minimum structural threshold for the old-growth stage after 74 years. Only 13 years was required for Wildcat Creek stand to reach the old-growth threshold. During the 45 years of simulation, the diameter distributions of both stands became broader and flatter. DBH distribution of dead trees had a general descending trend over the simulation in each stand. Gaps at Phelps were typically small after 45 years. Gap area at Wildcat Creek was somewhat more constant over the 45 years of simulation but a big gap was formed because of the death of several adjacent large trees.

• The Korean Journal of Ecology
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• v.15 no.4
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• pp.395-410
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• 1992

Disturbance regime and tree regeneration were studied in kwangnung natural forest, an old-growth deciduous hardwood forest located in central korea. This forest is dominated by carpinus laxiflora, c.erosa, and quercus species. The area occupied by canopy gaps was 4.6% of the total forested area, and the mean size of canopy gaps was 92 $m^2$ with the maximum being 524 $m^2$. More than half of the gaps were less than four years old, and 3/4 of the gaps were created by death of only or two canopy trees, indicating the dominance of small-sized gaps in kwangnung forest. about half of the gap-makers were c. laxiflora, and another one third were quercus species. In contrast, the most frequent relacers were c. laxiflora while quercus species filled only 5% of the gaps, suggesting a future shift in tree species composition under the current disturbance regime. tree regeration was more conspicuous even in small gaps than non-gaps regardless of shade-tolerance of tree species, indicating the importance of gaps in tree regeneration.

• Korean Journal of Environment and Ecology
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• v.17 no.2
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• pp.144-152
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• 2003

The purpose of this study was to investigate the effects of lime fertilization and light intensity on beech regeneration strategy in a mature beech forest(ca. 150 years old) gaps, which was located in the soiling areas Germany, where the soil is an acid brown earth. For the experiment canopy gaps of 30m diameter were cut, and one canopy gap remained as untreated while the other was limed(3t dolomite h $a^{-1}$). Soil chemistry, soil water potential, light intensity(PAR), ground vegetation, beech seedlings and mycorrhiza were investigated along transect from the stands into gaps to the north. The results of this study are followings: 1) In the limed gap, soil chemistry was greatly improved and a vigorous herb layer developed as compared to the unlimed gap. 2) Development and growth of the beech seedlings in the unlimed gap were generally deficient. Specially, developments of lateral roots were very lack. 3) Through the lime fertilization, the minerals contents of beech leaves such as calcium(Ca) and magnesium(Mg) were increased, while manganese(Mn) was decreased. There was antagonism between potassium(K) and calcium(Ca) or magnesium(Mg). 4) The relative mycorrhiza frequency(RM) in beech seedlings of the southern edge was very higher than that of the middle part, and through the lime fertilization extension of the species Laccaria amethystina appeared clearly. The results of this study showed that lime fertilize in forest, where the soil is acid, will be necessary..

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.1
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• pp.13-19
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• 2020

This study compared RGB color images with canopy light interception (LI) and leaf area index (LAI) measurements for low cost and low labor. LAI and LI were measured from vertical gap fraction derived from top of digital image in soybean canopy cover (cv Daewonkong, Deapongkong and Pungsannamulkong). RGB color images, LAI, and LI were collected from V4.5 stage to R5stage. Image segmentation was based on excess green minus excess red index (ExG-ExR). There was a linear relationship between LAI measured with LI (r²=0.84). There was alinear relation ship between LI measured with canopy cover on image (CCI) (r²=0.94). There was a significant positive relationship(r²=0.74) between LAI and CCI at all grow ingseason. Therefore, it is expected that in the future, the RGB color image could be able to easily measure the LAI and the LI at low cost and low labor.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.94-105
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• 2009

Black locust (Robinia pseudoacacia) stand is representative lowland exotic plantation with low ecological quality and arrested succession in South Korea. To facilitate succession and restore natural vegetation, small canopy gaps (${\sim}57m^2$), which can modify minimally structural variables and reduce restoration related disturbances on stand, was established in the black locust stand, and oak (Quercus serrata) seedlings were introduced in the gap. Two types of varying levels were introduced for gap creation; cutting (C) and girdling (G) on canopies. Understory removal (CU and GU) treatment was applied as subtypes of structural modification. Growth (diameter, height and leaf area) of target species and responses (species composition, diversity and coverage) of understory community were monitored during study years (2007~2008). Canopy openness was different significantly among treatments but not for light availability. Based on the result of logistic regression, growth of height and leaf area of seedlings were significant variables on seedling survival. Height and leaf area of seedlings were increased during study years, although radial growth was reduced. During study years, there were no significant differences in species composition and diversity, and total coverage increased about 20%. Increase of resources by gap creation and understory removal likely affect growth of target species. Small gap creation was effective to reduce understory responses in composition and diverstiy. Synthesized, growth of target species and responses of understory community to small canopy gap creation exhibited, in short term, possibility of utilization in alternative forest restoration and management option. Long-term monitoring is necessary to certificate effect of artificial gap creation on forest restoration.

• Journal of Korean Society of Forest Science
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• v.97 no.2
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• pp.165-170
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• 2008

Litterfall has been recognized an important part of the forest ecosystem production, playing a major pathway in energy flow and nutrient cycling through the ecosystem. This study was carried out to examine the quantity and components, temporal variation, and spatial heterogeneity of the litterfall in the mixed broadleaved-Korean pine forest. The data were collected from the 9ha permanent experimental plot, of which on the center area, i.e. $150m{\times}150m$, the total number of 319 circular litterfall traps with the size of $0.5m^2$ were established to collect falling litterfall. The results showed that the annual amount of litterfall was totalized 3,033.7 kg/ha, occupying broad-leaves of 39.3%, conifer-leaves of 29.5%, others of 18.5%, branches of 10.4%, and seeds of 2.3%. The peak point of the litterfall production was made at the end of September, proportionating 32.2% of total amount. The analysis of semivariogram revealed the existence of high spatial heterogeneity, calculated the scale of spatial heterogeneity ranged from 11.6 m to 29.1 m. The result of proportion (C/[Co+C]) showed that spatial heterogeneity of autocorrelation in total spatial heterogeneity were from 97.0% to 100%. The relatively heavy branches and others had significant differences in litterfall production between the areas of canopy gap and closed canopy in the 95% probability level, but the other components did not show statistical differences.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.621-627
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• 2006

This study was conducted to understand the pattern and characteristics of seed rain in the broadleaved-Korean pine mixed forest. We established 287 $0.5m^2$ circular seed traps and collected and identified fallen seeds in the traps every two weeks in $150m{\times}150m$ sample plot of the permanent nine hectare of experimental plot in 2005. The overall average density of seed rain was $864.2/m^2$. The seeds of Betula costata Betula costata had the highest number of fallen seeds as $676.0/m^2$ (78.2%), followed by Abies nephrolepis as $57.5/m^2$, B. platyphylla as $37.9/m^2$, Tilia amurensis as $32.2/m^2$, Acer ukurunduense as $17.0/m^2$, A. tegmentosum $14.8/m^2$, and so on. Pinus koraiensis was recorded only $2.5/m^2$ of fallen seeds mainly owing of Korean pine had low rate of purity due to the animal and microbiological predation. Most of seed dispersal have started from the middle to late August and come to an end on the middle of November. The peak time of seed dispersal varied depending on the species. The rate of pure seed by dispersal time varied according to the species, thereupon the aspect of predation and the rate of blasted seed which had influence on the rate of purity also varied according to the species. The density of Korean pine seed rain in the forest gap was significantly different at $P{\leq}0.05$ from in the closed canopy. But the other species had no difference among canopy coverage.

• Journal of Ecology and Environment
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• v.38 no.2
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• pp.175-183
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• 2015

Extremely strong winds and heavy rainfall caused canopy gaps in a mixed Abies holophylla broadleaf forest and a Quercus mongolica-dominated forest in Odaesan National Park, Korea in October 2006. The impact of the combination of strong winds and torrential rain on the development of forest gaps and canopy structures were investigated. The mean size of newly created gaps were $205m^2$ in the mixed forest and $86m^2$ in the Quercus forest, and were created by 2.8 and 1.4 gapmaker trees, respectively. Among the 73 trees lost in the mixed forest, 59% succumbed because of direct wind damage while 41% were struck by neighboring trees that fell into them. Most of these trees downed by wind were uprooted (74%), while the trees downed by neighboring tree falls snapped (78%). 21 trees in the Quercus forest died from direct wind damage, and 57% of them were uprooted. Although the relative density of Abies nephrolepis and A. holophylla represented only 0.2% and 6.4%, respectively, of all species in the intact mixed forest, they accounted for 27% and 15%, respectively, of all trees affected by wind on that site. In fact, 85% of the total A. nephrolepis and 91% of the total A. holophylla in the mixed forest fell directly due to strong wind. By contrast, only one Abies species, A. nephrolepis, was found in the Quercusdominated forest, and it accounted for 7.3% of the species composition. These findings suggest that A. nephrolepis and A. holophylla are particularly susceptible to high winds because of their great heights and shallow root systems.

• Journal of Forest and Environmental Science
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• v.29 no.4
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• pp.300-306
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• 2013

Based on the guiding ideology of "Close-to-nature forestry", the soil chemical properties of Korean pine (Pinus koraiensis) plantation forest which was early done by canopy gap control were analyzed of Liangshui nature reserve in northeastern China. The results indicated that the nurture of forestry crevice diaphanous tended to improve the soil nutrient contents and significant differences of soil nutrients existed among different levels of soil for the same forest type of Korean pine. At 0< $H{\leq}20$ cm layer, the content of available nitrogen, available phosphorus, available potassium, total nitrogen and total phosphorus in artificial pure Korean pine forest are 640.28 $mg{\cdot}kg^{-1}$, 7.54 $mg{\cdot}kg^{-1}$, 275.91 $mg{\cdot}kg^{-1}$, 1.114% and 0.075%, they all higher than the other kinds of forests and for average 1.1 times, 1.4 times, 1.3 times, 1.6 times and 1.2 times. From the layer of $0<H{\leq}20$ cm to 20 cm < $H{\leq}40$ cm, soil nutrient indicators showed various degrees of decreasing in which organic matter had the greatest decline, decreasing by 170.64% while PH had the lowest decline, decreasing by 4.66%.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.258-265
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• 1995

Regeneration process of edaphic pine(Pinus densiflora) climax forest in Bulyung-gyegog, Uljin-gun, Kyungsangbuk-do, was studied. The height of dominant trees in the stands are 12 15m. Upper layers are highly dominated by pine trees and are randomly distributed. Pine trees in lower layer grow in a patch type. In the upper layer, the age distribution is likely one model type with mode of 60 and 80 years. In the horizontal distribution of these trees, some of the even-aged cluster constituted of several tree were found. For the first 25 years, the stem diameter increment rates in upper layer are higher than those in the middle layer. It could be concluded that after the forest canopy had been broken out, the seedlings established densely in a patch in the gap with the decreasing density and some of them, distributed in random, would constitute the canopy.